1. Physical properties of minerals
GEC,BHUJ
Physical properties of minerals

2. Participates students
Name
Enrolment num
Kunal Thacker
Lakkad Venish
Jignesh Zala
Makavana Vijay
Gajendra Mal
Mali Dilip
Vishal Modh
Nadapara Shahil

3. Physical Properties of Minerals
Colour
Luster
Streak
Hardness
Crystal Form and Structure
Cleavage
Fracture
Specific Gravity

4. Colour
First thing the notice in mineral is colour. Colour is big reason to attract people but colour is not a good property to identification of minerals.
It is usually the first property to confuse to identification.
Colour arises due to electronic transitions, often of trace constituents, in the visible range of the EM spectrum.

5. Examples of colour

6. Luster
This property describes the appearance of reflected light from the mineral’s surface. Non-metallic minerals are described using following terms:
Adamantine- very gemmy crystals, like diamond.
Dull- just a non-reflective surface of any kind.
Fibrous- the look of fibres.
Vitreous- the most common luster, it simply means the look of glass.
Waxy- the look of wax.

7. Examples of luster

8. Streak
The colour of a mineral in its powdered form; obtained by rubbing the mineral against an unglazed porcelain plate.
Streak is usually less variable than colour.
Useful for distinguishing between minerals with metallic luster.

9. Example of Streak

10. Hardness
This is the resistance of the mineral to abrasion or scratching. This property doesn't vary greatly from sample to sample of the same mineral, and thus is highly diagnostic.
It also is a direct reflection of the bonding type and internal atomic arrangement.
A value is obtained by comparing the mineral to a standard scale devised by Moh, which is comprised of 10 minerals ranging in hardness from talc (softest) to diamond (hardest).

11. Moh’s Hardness Scale

12. Crystal Form and Structure
The external morphology of crystals generally reflect the internal arrangement of their constituent atoms.
This can be obscured, however, if the mineral crystallized in an environment that did not allow it to grow without significant interaction with other crystals.

13. Example
Chrysotile
Asbestos

14. Example
Crystal Forms: Quartz

15. Example
Feldspar

16. Cleavage
Orientation and number of planes of weakness within a mineral.
Directly reflects the orientation of weak bonds within the crystal structure.
This feature is also highly diagnostic.

17. Examples of cleavage

18. Fracture
This describes how a mineral breaks if it is not along well defined planes.
In minerals with low symmetry and highly interconnected atomic networks, irregular fracture is common

19. Examples of Fracture

20. Specific Gravity
Density refers to the mass per unit volume. Specific gravity is the relative density. In CGS units density is grams per cm3 and water density is 1g/cm3.
Specific gravity would have the same numerical value has density, but no units.
Specific gravity can usually be qualitatively measured by the heft of a mineral, in other words those with high specific gravities usually feel heavier.
Most common silicate minerals have a specific gravity between about 2.5 and 3.0.

21. Examples of Specific Gravity